The present invention relates to method of, and apparatus for, the production of feeders for manufacturing glass fibers. More particularly this invention relates to the orificed section or tip plate of the feeder.
The orificed feeder floor which has tips or projections is generally made of a high temperature alloy such as a platinum and rhodium alloy. In the production of a tip plate the tips or projections are machined to a finished height. Care must be taken in the machining of the thin projection walls as they can distort and burr over when subjected to even a minimal tooling pressure. Thus, electrical discharge machining has been used for machining the projections to finished height. Electrical discharge machining, or EDM, operates on the principal of disintegrating metal with electrical energy. An electrode is fitted into a chuck of a EDM machine and lowered to within a few thousandths of an inch of the work piece. Electrical arcs are produced in the space between the electrode and the workpiece. There are essentially no machining forces produced by the EDM'ing because the electrode never touches the workpiece.
Although the EDM process has been used, it has some drawbacks. One disadvantage is its relatively slow production rate as compared to conventional machining or cutting operations. Another disadvantage is that the disintegrated precious alloy removed from the projections in the EDM machining operation is difficult to separate and recover from the disintegrated material from the EDM electrodes. Recovery of the machined off alloy is economically very important to the plate finishing operation.
Improved method and apparatus for finishing a plate are needed.